详解Android中Libgdx使用ShapeRenderer自定义Actor解决无法接收到Touch事件的问题

package com.ef.smallstar.unitmap.widget;

import android.content.res.Resources;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.graphics.g2d.Batch;
import com.badlogic.gdx.graphics.g2d.BitmapFont;
import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
import com.badlogic.gdx.scenes.scene2d.Actor;
import com.ef.smallstar.EFApplication;
import com.ef.smallstar.R;

/**
 * Created by ext.danny.jiang on 17/4/17.
 *
 * A Widget currently used in the UnitMap, shown as a CIRCLE shape
 * if text not null, there would be a text drawn in the center of the circle
 */

public class CircleActor extends Actor {

  private float centerX;
  private float centerY;
  private String text;
  private float radius;

  private ShapeRenderer sr;
  private BitmapFont bitmapFont;

  public CircleActor(float x, float y, float radius) {
    this(x, y, radius, null);
  }

  public CircleActor(float x, float y, float radius, String text) {
    this.centerX = x;
    this.centerY = y;
    this.radius = radius;
    this.text = text;

    sr = new ShapeRenderer();
  }

  @Override
  public void act(float delta) {
    super.act(delta);
  }

  @Override
  public void draw(Batch batch, float parentAlpha) {
    ...

    batch.end();

    sr.setProjectionMatrix(batch.getProjectionMatrix());
    sr.setTransformMatrix(batch.getTransformMatrix());

    sr.begin(ShapeRenderer.ShapeType.Filled);

    sr.circle(centerX, centerY, radius);

    sr.end();

    batch.begin();

    ...
  }

Stage stage = new Stage();

CircleActor ca = new CircleActor(100, 100, 50, "Hello World");
ca.addListener(new ClickListener(){
  public void click(){
    Gdx.app.log("TAG", "ca is clicked");
  }
})

stage.add(ca);

sr.setProjectionMatrix(batch.getProjectionMatrix());
sr.setTransformMatrix(batch.getTransformMatrix());

public EfCircle(float x, float y, float radius, String text) {
    this.centerX = x;
    this.centerY = y;
    this.radius = radius;
    this.text = text;

    //解决ShapeRenderer无法获取Touch事件
    setPosition(centerX - radius, centerY - radius);
    setSize(radius * 2, radius * 2);

    sr = new ShapeRenderer();
  }